Tape printing devices for printing letters, etc. on a label tape (having a plurality of labels temporarily stuck on the front side of a long strippable sheet being aligned along its length) are well known today. In regard to such tape printing devices, a variety of configurations, for detecting marks (position indication marks) formed on the back side of the label tape by use of a mark sensor and carrying out feeding control of the label tape based on the detection of the position indication marks, have been proposed (e.g. Japanese Patent Provisional Publication No. 2000-168181).